The instant invention relates to medical devices and more particularly to a surgically implantable electrical access port for conducting electrical energy to a predetermined location in the body of a patient.
A number of surgically implantable electrically powered medical devices have been developed over the course of the last few decades. The most common of these devices is the battery-powered heart pacer which is surgically implantable in the body of a patient so that it is operative for stimulating the heart muscle to operate with a regular repetitive beating pattern. It has been found that heart pacers only require a few microwatts of electrical energy to operate and hence they are generally capable of operating for periods of up to two years or more without replacing the batteries thereof. Nevertheless, it has been found that it is generally necessary to periodically surgically replace the batteries of devices of this type throughout the lives of patients in which they are installed. In addition to heart pacers, a number of other electrically powered devices have been developed for treating various medical conditions. However, many of these devices have been found to require several watts of electrical power to operate and hence they have required relatively large batteries which cannot practically be surgically implanted in patients. Accordingly, the only alternative has been to power devices of this type through external power sources, but since this practice severely limits the mobility of patients, it has normally only been used in extreme cases.
The instant invention provides an effective electrical access port assembly which is operative for supplying electrical energy to a predetermined location in the body of a patient in order to recharge an electrical storage battery and/or to power an electrically operated medical device implanted in the patient. Specifically, in its preferred form, the access port assembly of the instant invention comprises a surgically implantable body portion having first and second enclosed electrically insulated cavities therein, the body portion including first and second septa which are self-sealingly penetrable for gaining access to the first and second cavities, respectively, first and second electrical contacts in the first and second cavities, respectively, and first and second surgically implantable, insulated electrical conductors electrically connected to the first and second contacts, respectively. The access port assembly further comprises first and second electrically conductive needles, each including an elongated electrically insulated shank portion and an electrically exposed tip portion. The septa are adapted so that they are self-sealingly penetrable by the first and second needles for electrically connecting the tip portions of the needles to the first and second contacts, respectively, in a manner wherein the tip portions are located entirely within their respective cavities, and hence electrically insulated from the area surrounding the body portion. The access port assembly preferably further comprises an electrically insulated partition in the interior of the body portion which is substantially impenetrable by the needles and separates the first and second cavities. Each of the electrical contacts preferably comprises a contact brush including a plurality of closely spaced, substantially parallel, resilient, electrically conductive brush elements which are aligned so that the tip portion of a needle is receivable in engagement between a portion of the brush elements when the needle is inserted into the appropriate cavity in the body portion.
It has been found that the access port assembly of the instant invention can be utilized for effectively conducting electrical energy to a predetermined location in the body of a patient for either recharging a surgically implanted battery or for powering an implanted electrically powered medical device. Specifically, once the body portion and the conductor wires have been surgically implanted in a patient so that the body portion is located beneath the skin of the patient and the conductor wires extend to a predetermined location in the patient's body, the electrically conductive needles can be inserted through the skin of the patient so that they pass into the cavities through the septa in order to electrically connect the tip portions of the needles to the contacts in the cavities. Thereafter, by connecting the needles to an electrical power source, electrical energy can be supplied to the contacts in the body portion through the needles and then passed through the conductor wires to the predetermined location in the patient's body. As a result, it is possible to periodically recharge an electrical storage battery implanted in the body of a patient by periodically supplying electrical energy thereto through the access port so that the battery can remain in the body of the patient for an extended period of time without replacement. Further, it is practical to surgically implant a medical device which requires a relatively large amount of electrical energy in the body of a patient since the battery of the device can be recharged at regular intervals without invasive surgery. Still further, it is possible to periodically directly supply electrical power to an electrical device surgically implanted in the body of a patient without invasive surgical procedures.
Accordingly, it is a primary object of the instant invention to provide an access port assembly for supplying electrical energy to a predetermined location in the body of a patient.
Another object of the instant invention is to provide a means for recharging an electrical storage battery surgically implanted in the body of a patient.
An even further object of the instant invention is to provide an access port assembly comprising a surgically implantable body portion having a penetrable septum therein, an electrical contact in the body portion, a surgically implantable insulated electrical conductor wire connected to the electrical contact and an electrically conductive needle having an insulated shank portion and an uninsulated tip portion wherein the tip portion is electrically connectable to the contact in the body portion to supply electrical energy to the conductor wire.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.